Bollworm

Bollworm is presented not simply as a cotton pest, but as a measure of how chemical control can reverse its own purpose. In the irrigated cotton fields of the Gash Delta, more intensive DDT spraying was followed by more bollworms and greater crop damage; in Louisiana, a different broad-spectrum insecticide aimed at fire ants helped unleash the sugarcane borer. Together, these examples show how killing insects indiscriminately can favor the very agricultural losses a control campaign is meant to prevent.

The Gash Delta cotton fields

About 60,000 acres of cotton were grown under irrigation in the Gash Delta. Early trials of DDT seemed successful, and spraying was intensified. The turn came with the bollworm: as more cotton was sprayed, more bollworms appeared. The account does not treat this as a minor complication alongside an otherwise successful campaign; it makes the increase in the pest the central reversal.

The contrast between treated and untreated fields sharpened the point. Unsprayed cotton suffered less damage to its fruits and, later, its mature bolls than sprayed cotton. In fields sprayed twice, seed-cotton yield dropped significantly. Although treatment eliminated some leaf-feeding insects, that gain was more than offset by bollworm damage. The practical result was that growers would have obtained a better cotton crop by avoiding the spraying expense and labor altogether.

How chemical control reverses itself

The book places the cotton example within a broader account of changing insect populations. A pesticide may suppress some insects while disturbing the relationships that had limited others. In the Gash Delta, spraying did not simply remove a pest from a crop; the heavier treatment coincided with the appearance of more bollworms and a poorer yield. The comparison across sprayed and unsprayed cotton makes the costs visible in the crop itself.

A second example, from Louisiana in 1957, clarifies one mechanism behind such reversals. The United States Department of Agriculture's fire-ant eradication treatment used heptachlor across farmland. Soon afterward, damage from the sugarcane borer increased sharply. The chemical intended for the fire ant had killed the borer's enemies, allowing a serious sugarcane pest to flourish. Farmers considered suing the state for negligence because they had not been warned that this consequence might follow.

Significance in the account of pesticides

Bollworm's role in the narrative is evidentiary: its increase makes the consequences of intensified spraying legible in terms of damaged fruit, mature bolls, and diminished harvest. The account does not attribute the rise to a single fully specified biological process; it establishes the pattern through the contrast between sprayed and unsprayed fields and the poorer results where spraying was repeated. That distinction keeps the example grounded in the reported agricultural outcomes.

Set beside the Louisiana sugarcane-borer episode, the Gash Delta case broadens the argument from one crop and one chemical to a recurring hazard of broad lethal treatment. Suppressing selected insects can remove checks on other pests, so the target of a campaign is not necessarily the only insect population it changes. Bollworms thereby embody the book's central agricultural warning: an intervention intended to protect crops may instead intensify the damage and leave growers worse off than before.